//Zachary Fitzsimmons
import java.util.*;
public class Person
    implements Comparable<Person>
{
  private String first, last;
  
  public Person()
  {
    first = "";
    last = "";
  }
  public Person(String f, String l)
  {
    first = l;
    last = f;
  }
  public int compareTo(Person p2)
  {
    return last.compareTo(p2.last);
  }
  public String toString()
  {
    return new String(last +", "+first);
  }
}